Featured Research

from universities, journals, and other organizations

Ion armageddon: Measuring the impact energy of highly charged ions

Date:
August 31, 2011
Source:
National Institute of Standards and Technology (NIST)
Summary:
Much like a meteor impacting a planet, highly charged ions hit really hard and can do a lot of damage, albeit on a much smaller scale. And much like geologists determine the size and speed of the meteor by looking at the hole it left, physicists can learn a lot about a highly charged ion's energy by looking at the divots it makes in thin films. Researchers have now measured the energy of highly charged ion impacts on a thin film surface for the first time in detail.

A schematic detailing the various ways that the energy of highly charged ions is dissipated during an impact. Approximately 60 percent of the ion’s energy is blown back and, according to NIST measurements, 27 percent of the remaining 40 percent goes into deforming the material—making a crater or “divot”.
Credit: NIST

Much like a meteor impacting a planet, highly charged ions hit really hard and can do a lot of damage, albeit on a much smaller scale. And much like geologists determine the size and speed of the meteor by looking at the hole it left, physicists can learn a lot about a highly charged ion's energy by looking at the divots it makes in thin films.

Building upon their work for which they were recently awarded a patent, scientists at the National Institute of Standards and Technology (NIST) and Clemson University have measured the energy of highly charged ion impacts on a thin film surface for the first time in detail. Understanding how ions discharge their energy upon impact will help researchers to make better predictive models of how the particles affect surfaces.

The question isn't trivial. Ions are used in exactly that way for a variety of micro- and nanoscale production processes, techniques such as ion milling and etching. Better predictive models may also help researchers curtail ionic erosion where it would be a bad thing, such as inside a fusion reactor.

The research team used xenon atoms from which they had stripped all but 10 of the atoms' original 54 electrons. Making an atom so highly ionized takes a lot of energy -- about 50,000 electron volts. The atom soaks up all the energy that went into freeing the electrons until it is capable of imparting more energy, and thus more damage, than could be done with kinetic energy -- mass and speed -- alone.

"When the highly charged ion is finally released and hurtles into its target, most of its energy, about 60 percent, blows back in the 'splash' and dissipates into the vacuum," says Josh Pomeroy. "According to our measurements, 27 percent of the remaining 40 percent of the ion's energy goes into changing the shape of the material -- making divots."

Pomeroy says that the remaining 13 percent is most likely converted to heat.

The group first began looking into nanoscale pitting of thin films to help improve the performance of data storage hard drives, which used aluminum oxide thin films as an insulator between magnetic plates. They used ions to pockmark the surface of these films and showed that the depth of the pitting could be determined by measuring minute changes in electrical conductance through the film.

The original motivation for the work has abated, but the group's method and materials remain useful for measuring the energy transfer of highly charged ions and calibrating industrial systems using high-energy ion beams.


Story Source:

The above story is based on materials provided by National Institute of Standards and Technology (NIST). Note: Materials may be edited for content and length.


Journal Reference:

  1. R. Lake, J. Pomeroy, H. Grube, C. Sosolik. Charge State Dependent Energy Deposition by Ion Impact. Physical Review Letters, 2011; 107 (6) DOI: 10.1103/PhysRevLett.107.063202

Cite This Page:

National Institute of Standards and Technology (NIST). "Ion armageddon: Measuring the impact energy of highly charged ions." ScienceDaily. ScienceDaily, 31 August 2011. <www.sciencedaily.com/releases/2011/08/110831115814.htm>.
National Institute of Standards and Technology (NIST). (2011, August 31). Ion armageddon: Measuring the impact energy of highly charged ions. ScienceDaily. Retrieved April 24, 2014 from www.sciencedaily.com/releases/2011/08/110831115814.htm
National Institute of Standards and Technology (NIST). "Ion armageddon: Measuring the impact energy of highly charged ions." ScienceDaily. www.sciencedaily.com/releases/2011/08/110831115814.htm (accessed April 24, 2014).

Share This



More Matter & Energy News

Thursday, April 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Obama Plays Soccer With Japanese Robot

Raw: Obama Plays Soccer With Japanese Robot

AP (Apr. 24, 2014) President Obama briefly played soccer with a robot during his visit to Japan on Thursday. The President has been emphasizing technology along with security concerns during his visit. (April 24) Video provided by AP
Powered by NewsLook.com
Obama Encourages Japanese Student-Scientists

Obama Encourages Japanese Student-Scientists

AP (Apr. 24, 2014) President Obama spoke with student innovators in Japan and urged them to take part in increased opportunities for student exchanges with the US. (April 24) Video provided by AP
Powered by NewsLook.com
UN Joint Mission Starts Removing Landmines in Cyprus

UN Joint Mission Starts Removing Landmines in Cyprus

AFP (Apr. 23, 2014) The UN mission in Cyprus (UNFICYP) led a mine clearance demonstration on Wednesday in the UN-controlled buffer zone where demining operations are being conducted near the Cypriot village of Mammari. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com
Air Force: $4.2B Saved from Grounding A-10s

Air Force: $4.2B Saved from Grounding A-10s

AP (Apr. 23, 2014) Speaking about the future of the United States Air Force, Chief of Staff Gen. Mark Welsh says the choice to divest the A-10 fleet was logical and least impactful. (April 23) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins